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CHAPTER 3 CPU
3.1.1 Specific-purpose Areas
In addition to the I/O area, the general-purpose register area and vector table area are
available as areas for specific applications.
■ General-purpose Register Area (Address: 0100
H
to 01FF
H
)
• This area is used for 8-bit arithmetic operations and transfer. Supplementary registers are provided.
• Since this area is allocated to a part of the RAM area, it can also be used as normal RAM.
• When this area is used as a general-purpose register, it can be accessed faster using shorter instructions
by general-purpose register addressing.
For details, see Section "3.2.2 Register Bank Pointer (RP) " and Section "3.3 General-Purpose Registers ".
■
Vector Table Area (Address: FFC0
H
to FFFF
H
)
• This area is used as vector tables of the vector call instructions, interrupts, and reset.
• This area is allocated to the highest ranges of the ROM area, and the start address of the corresponding
processing routine is set to the address of each vector table.
Table 3.1-1 provides the reference addresses in the vector table that correspond to the vector instructions,
interrupts, and reset.
For details, see Section "3.4 Interrupts ", Section "3.5 Reset ", and "CALLV #vct" in APPENDIX "B.2
Special Instructions ".
Table 3.1-1 Vector Table (1/2)
Vector call instruction
Address in the vector table
Upper digits Lower digits
CALLV #0
FFC0
H
FFC1
H
CALLV #1
FFC2
H
FFC3
H
CALLV #2
FFC4
H
FFC5
H
CALLV #3
FFC6
H
FFC7
H
CALLV #4
FFC8
H
FFC9
H
CALLV #5
FFCA
H
FFCB
H
CALLV #6 FFCC
H
FFCD
H
CALLV #7
FFCE
H
FFCF
H
IRQF FFDC
H
FFDD
H
IRQE FFDE
H
FFDF
H
IRQD FFE0
H
FFE1
H
IRQC FFE2
H
FFE3
H